Dubai - WAG - Gyro down 9.12.15

Would a 50-hour P-51 pilot be allowed to fly the Reno Air race? Would a SENSIBLE 50-hour P-51 pilot do it even if allowed to?

The "let Darwin sort it out" crowd ignore the fact that, when someone "offs" himself in a gyro front of a crowd and media, we each are hurt as well. Gyros already have the reputation in the rest of the aviation world of being "touchy" and prone to flipping out of control without warning. More of that we (the surviving gyro pilots) don't need.

Then there are the design issues. They've already been beaten to death in this thread. Warning people in the Operating Manual about torque roll instead of fixing it is a conscious design decision. Don't get me started...
 
Sometimes common sense is in short supply and there are some people that need rules and regulations to save them from themselves.

No absolutely not - Darwin needs his followers.

Rules and regulations are not the answer for morons who will kill them selves anyway.
 
Warning people in the Operating Manual about torque roll instead of fixing it is a conscious design decision. Don't get me started...

Doug, the trouble is unless you are prescribing a pair of counter rotating propellors to cancel the torque, I know of no scheme that effectively cancels the torque in a high speed hard slip.Differential tail lift works in straight flight but in extreme slips the torques will not be canceled.

Nevertheless, while I can see your point there is a counter argument: One would rather always be aware of the torque in all flight conditions and get into the habit/reflex of canceling it out than be suddenly reminded of it during an extreme situation.

Bottom line, high speed hard slips in any gyro (LTL,CTL, HTL) followed by moving the stick hard in the flight direction (as performed by this pilot) can topple you. The high speed-hard slip combination reduces the pitch stability provided by the tail or even LTL as they are most effective only when the fuselage is pointing in the direction of travel. Further, the slip moves the prop slip stream away from any differential tail planes. It does not take much movement of the stick in the direction of fight to unload it during this reduced pitch stability regime.

I believe high speed hard slips should be avoided (in all gyros) just as rapid pitch down after zoom climbs and other low g maneuvers.
 
Don't be silly CB! No connections (me or family) with any gyro manufacturer. Can you say the same? Also never ever plan to be involved in the business side of aviation. I make a good living doing other things.

CB, I started my quest of understanding gyroplanes by reading your posts and learnt a great deal. For this I will always be thankful.

The simple theory of PPO (that you pioneered) and torque roll is a good one and can explain a great deal of the historic accident record and unfortunately some today as well. Like all theories though it has its limits. It is limited in its predictions to HTL gyros without significant HS. For gyros with significant HS Volume ( e.g. Magni clone), a more complete analysis is required. And to my regret you have never been willing to get into this. Instead you have repeatedly pushed the PPO theory as the final word on stability, and attacked (personally) people who do not agree with it. Why?

A more complete analysis will show that significantly HTL gyros can be made pitch stable with the use of a stab. The results I have got are very similar to what Jean Fourcade got in post 137 in this thread:http://www.rotaryforum.com/forum/showthread.php?t=43986&page=10

In that example the gyro is just under 8" HTL, but still is found to be stable when the complete analysis is made (as opposed to a single degree of freedom as in the PPO model) which indicates it will PPO.
 
This thread has taken a very, very unpleasant turn.

The forum has always been unkind to people who aren't considered "one of the gang" but some of the recent posts are really taking things to a new low.
 
With a 150 mph propeller induced velocity and 30 mph 90º yaw component, the center of the propeller slipstream is deflected ~11º; deviating from the tailplane center by ~0.6 ft if it’s 3 ft downstream of the prop. Still pretty effective in balancing torque.

No problem if the sideways center of pressure of the fuselage is sufficiently high so as not to create slip-roll coupling.

And like you Raghu, I’ve never had a financial stake in aviation. I earned my living doing this:

https://www.google.com/search?tbo=p...:Charles+ininventor:A+ininventor:Beaty&num=10

Ignore Kirk’s stuff.
 
Bloodyell CB, now i KNOW im just a scg. :(

Warning people in the Operating Manual about torque roll instead of fixing it is a conscious design decision. Don't get me started...
But Doug, writing it is much cheaper, shifts the resposability and avoids the need for any actual understanding of the issue.
 
Unfortunately Birdy, the days of homebuilding and experimental aviation are gone forever. No one still knows how to weld or do aircraft fabric.

Our FAA looks the other way and licenses knocked down factory gyros as EAB (experimental- amateur built). The current crop of “homebuilders” needs factory assistance just to stick bolts in their holes.

To such people, the upholstery is more important than the rotor.
 
Chuck, to me it looks like evolution , I my self knew nothing when I started designing and building gyros so everything was built and first tested to destruction , since I had never heard about sandbagging to check for g load testing my early machines were hung from a tripod fully loaded with me in the seat by two ropes of different lengths, the short rope was cut and the machine fell til it was stopped by the longer rope, this was repeated with each drop being longer until the g meter attached to the mast read four Gs or something bent or broke, more evolved people could do this on paper and later on computer, to me the building and testing was as much fun and educational as flying the machines. I think there will come a sad day when people build and fly a machine in a computerized simulator .
Norm
 
A divergent opinion.

A divergent opinion.

Unfortunately Birdy, the days of homebuilding and experimental aviation are gone forever. No one still knows how to weld or do aircraft fabric.

Our FAA looks the other way and licenses knocked down factory gyros as EAB (experimental- amateur built). The current crop of “homebuilders” needs factory assistance just to stick bolts in their holes.

To such people, the upholstery is more important than the rotor.

I just returned from ROTOR and saw lots of thought and fabrication skills that had gone into many of the gyroplanes there. I saw the same at Bensen days.

Dr. Bensen’s stated goal was to design an aircraft that anyone could build and fly even if they didn’t know anything about how an autogyro worked and didn’t know how to light a welding torch.

If I were building a Bensen Gyrocopter in the 60s I would have sought out friends who knew more than me and had better fabrication skills to assist me.

I don’t see a lot of difference in what is going on today in the world of experimental aircraft other than helpers get paid for their skills/knowledge (builder assist) and the resulting aircraft has more capability.
 

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gaining experience

gaining experience

I have seen several references in this thread to the low level of experience (very few hours) of the accident pilot. I don't disagree with the general idea that novices shouldn't race, but I don't think it says enough. Personally, I doubt that 100 more hours of pattern work, local rides for friends, and hops to a nearby place for lunch would have made much difference. Would that sort of hour-building allow a pilot to approach and safely return from the edges of the safe envelope to create a real learning opportunity, and save his bacon in the race?

I would be interested to hear what others think should be the proper preparation for somebody who wants to do a pylon race. What experience(s), that could be obtained without undue risk, would offer enough judgment/skill development to undertake such a race prudently? How do you prepare someone for losing a helmet, for example?

Opinions welcome . . .
 
I think the only way to move from being able to fly a gyro to advanced maneuvers is to go a little at a time until you reach your goal or scare your self, when the scary point is reached you need to think about why it was scary and if you were in fact approaching a real danger zone and use common sense to decide your next practice session , all of this will take time, as for a helmet coming off it should be treated as any other failure in any aircraft, fly the machine first, don't focus on the failure, deal with it after you have determined that you still have a fly able machine, if it's something that you can't do anything about then you land as soon as possible, if it's as simple as a seat belt that came undone and you have another pilot ask him to fly while you retrieve the belt and refasten it, most important don't panic and make a small thing into a crash.
Norm
 
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I have several times proposed that PRA organize an "Advanced Skills" course for gyro pilots. That would be one way to increase the knowledge and skill level within our community. I can't say whether a course like his would have prevented that accident, had the pilot passed it. I am positive, however, that it would have improved his chances considerably. The syllabus I developed includes high speed maneuvering.

Greetings, -- Chris.
 
I think besides all the tech pissing matches on design, the answer to this accident is very clear. The pilot should not have been pylon racing in a world competition with so few hours on him as PIC. His judgment to participate in the contest was poor honestly.

It didn't help one bit that his helmet came right off of his head which means it might not be a properly secured helmet or the helmet design wasn't that great for security to begin with.
 
Hi, Raghu:

I agree that the high-speed slip is a difficult nut to crack. We shouldn't conclude that it is impossible to crack without trying really hard first.

The span of the tail planes and their distance from the prop bear on the question. If the damn HS needs to have a seven-foot span and be snugged in close to the prop, so be it. There is also the possibility of using dorsal fins (including wide mast fairings) to provide some slip-roll coupling in the stable direction. It's been done; Cierva even mounted one such fin above the rotor hub.

Raise your hand if you are, or have been, experimenting along these or similar lines? (Nope, mine isn't up, either).

I've related an incident involving a hard, fast slip here a couple times. A student who was accustomed to lightly-loaded UL fixed-wing planes put my Tandem Dominator into a stomp-and-yank slip at high power and about 85 mph. Nothing untoward happened, except that I could feel air blowing by my face sideways and the event just about relocated my upwind eyeball to the downwind side. There was no excursion in pitch or roll. Just a yaw and a hard slip. This is by no means a controlled experiment, just an anecdote, but it suggests one possible direction for organized experimentation.
 
It is possible to build gyros that don't flip when the pilot does something wrong:

my testing program involved full rudder deflection from full left to full right at FULL throttle and max speed.. the sideslips were about 75 degrees either way. the result was a significant speed loos (from 100 to 50 Mph).. nothing else. Also side slips of almost 90 degrees with high nose up were tested at full power... and then chopped the throttle. the result was the gyro started dropping tail first and immediately the nose flipped to flight direction with 45 degrees nose down picking up speed. the recovery height loss was about 50 feet.

unloading the rotor at full power was also tested gradually. i could not unload the rotor with normal 50% forward stick movement.. i had to sharply push the stick full forward. The result?? immediately the stick started slapping the inside of my legs.. so strong that i had to release forward force on it. As soon as the forward force was released everything was back to normal. No roll or push over tendency. some one who understand ROTOR aerodynamics and dynamics can understand why the rotor WARNED before it punished me.

There are lots of videos showing me putting our gyroplanes in the corners of the envelop.... the bottom line is:

Designing (or just copying) an aircraft to promote sales than safety is unethical!!!! First design safety and THEN promote sales. This is Aviomania's first objective.
 
There is also the possibility of using dorsal fins (including wide mast fairings) to provide some slip-roll coupling in the stable direction. It's been done; Cierva even mounted one such fin above the rotor hub.
My J-2 had one.
The prototype had a fairly narrow (front to back) mast fairing and wheel pants; the production models had a fin between the mast and the prop, and no wheel pants, which shifted the distribution of surface area upward.
 
I have built some enclosed machines that I had to put a fin around the mast to tame a really nasty slip roll that tried to kill me before I got it sorted out. Gyro boats need these and lots of horizontal stabilizer to stabilize the hull which is a lot of drag in a slip.
Norm
 
We had to demonstrate that no uncontrollable slip-roll coupling exists in the ArrowCopter by applying full rudder deflection in either direction while flying at 160 km/h (top of green arc).

Greetings, -- Chris.
 
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